Jack



y 3, 1934- H. H. ROBINSON 1,958,114

JACK

Filed March 27, 1935 IN VEN TOR. HA HOLD HROB/NSON BY WWW ATTORNEYS.

Patented May 8, 1934 STATES PTNT FFEE JACK Application March 27, 1933, Serial No. 662,943

2 Claims.

This invention relates to a jack or supporting mechanism for carrying the weight of the forward end of a semi-trailer when the latter is uncoupled from its tow car. Semi-trailers of this 5 type generally have a pair of rear wheels and a tapering front end terminating in a vertical pivot adapted to be received in a suitable socket in the tow car. Whenever the tow car is uncoupled it is necessary to provide a support for the wheelless front end of the semi-trailer in order to keep it at a substantially normal level. One object of the present invention is to provide a support of this character in which a substantial ground contact area is presented without interfering with the capability of the device for being folded compactly out of the way when not in use. An additional object is to provide a folding support of this general character which will not materially diminish the underfrai clearance of the semitrailer when the support is folded up out of the way. An additional object is to provide a support of this general character upon which the semi-trailer may be moved in any direction, if desired, after the tow car has been disconnected. Additional objects will appear from the following description and claims.

Referring to the drawing:

Fig. 1 is a side elevation of a semi-trailer having its front end carried by a supporting mecha- 30 nism constructed in accordance with this invention;

Fig. 2 is a front end elevation thereof;

Fig. 3 is a detail plan view, taken on a larger scale, illustrating the manner in which one of the supporting mechanisms is mounted;

Fig. 4 is a side elevation of the mechanism shown in Fig. 3, looking in the direction of the arrows on line 4-4 of that figure;

Fig. 5 is a front elevation of the mechanism shown in Figs. 3 and 4;

Fig. 6 is a detail corresponding to Fig. 4 but showing the parts in the positions they assume when the support is folded to inoperative position; and

Fig. 7 is a detail showing a removable portion of the support.

The serni-trailer is indicated generically in the drawing by the numeral 10, and is shown in broken lines. A jack or support, indicated generically at 11, is located at each of the forward lower corners of the semi-trailer. The two jacks are similar, save for an interchange of right and left, and a description of one will sufiice for both. Each jack is supported on three brackets 12, 13 and 14. The first two are generally similar in character, and are provided with flanged tops 15 and 16 respectively, which fit around the front lower frame cross member 17 of the semi-trailer and are attached to said cross member by bolts or rivets 18 passing through holes in the flanges. so Each of these brackets 12 and 13 is also provided with depending ears 20 through which are formed holes 21 adapted to receive a pivot pin 22. The

bracket 14 has a U-shaped upper flanged portion 25 adapted to straddle a cross member 26 of the 55 semi-trailer lower frame. Holes through the flange 25 permit the passage of bolts or rivets 28 by which the bracket is secured to the cross memher. On its lower side the bracket 14 is provided with depending spaced wings 29 through which are drilled holes 30 and 31 for a purpose to appear.

The support itself is composed of two units, a frame intended for permanent association with the frame of the semi-trailer and adapted to be swung out of the way when not in use, and a foot portion which is removed from the support a..- sembly so that maximum road clearance will be provided when the semi-trailer is coupled to the tow car. The swinging frame is composed of a vertical strut 35 and an angular strut 36 welded to it at 37. The upper ends of these struts are formed to fit between the ears 20 of brackets 12 and 13 and are provided with holes in al gnment with the holes 21 in those cars. Through these aligned holes pass the pivot pins 22 so that the frame is permitted to swing forward and back upon these pins as centers.

The lower end of the strut 35 is formed with a transverse hole extending in a direction parallel to the axis of rotation of the frame. The strut is adapted to fit within a hole 41 in a center post 42 formed in a foot 43 having a spherical ground engaging surface, a transverse hole 44 in the post registering with the hole in the strut when the parts are assembled. A slanting strut 45 is welded at 46 to the post 42 so as to form an integral part of the foot, and extends upwardly between the wings 29 of the bracket 14. When assembled a hole 4'? in the strut registers with the holes 30 in the wings, so that the parts can be held tightly together by a. pin 48 passing through the hole 44 and the hole in strut 35 which registers with it, and by a pin 49 passing through the registering holes 30 and 47.

When the supports are in use the feet 43 present a large area to the ground, preventing them from sinking in. By reason of this broad contact the front end of the semi-trailer can be moved around upon the support in any direction as if mounted on skids. It will also be observed that the feet carry the weight of the semi-trailer directly upon the struts 35, and that they are braced laterally and longitudinally of the vehicle by the struts 36 and 45 respectively. In order to give ample rigidity these struts are preferably inclined at an angle of substantially 45. When the semitrailer is again coupled to its tow car the pins 48 and 49 are taken out and the assemblies comprising the feet 43 and the attached struts 45 are removed to be stored temporarily in some con venient place, as for example, the rear compartment of the tow car. This removes all bulky parts from the supports, and the frames 35-36 can be folded up flat against the bottom of the semi-trailer. In the folded position of the frames the holes 40 are brought into registry with the holes 31 in the wings 29, so that the frames may be held by passing the pins 49 through these aligned holes.

What I claim is:

1. In a front support structure for semi-trailers when detached from their tow cars, a pair of support units laterally spaced one from the other at the forward end of the semi-trailer, each support comprising a foot having a spheroidal ground engaging surface, a substantially vertical strut releasably secured to the foot and adapted to carry the direct weight of the semi-trailer, a diagonal strut extending from the foot upwardly and rearwardly and attached at its lower end to the foot and releasably secured at its upper end to the semi-trailer, and a diagonal strut extending from the vertical strut, at a point adjacent the foot, upwardly and laterally towards the similar strut at the opposite side of the semi-trailer, said diagonal struts being positively connected both to the foot and to the semi-trailer and transmitting strains in all directions so that the forward end of the semi-trailer can be pushed over the ground in any desired direction.

2. In a front support structure for semi-trailers when detached from their tow cars, a foot having a spheroidal ground engaging surface, and having a vertically opening socket, a V-shaped frame having one leg vertical, a releasable connection between the frame and socket, hinges connecting the upper ends of the V-shaped frame to the semi-trailer whereby said frame may be swung into a vertical position when in use and into a horizontal position when not in use, a strut secured at its lower end to the foot, a bracket secured to the frame, a releasable connection between the strut and said bracket, and means for connecting the frame to the bracket when said foot and the strut have been removed.

HAROLD H. ROBINSON. 

